<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>发光按钮</title>
    <style>
      body {
        background-color: #000;
      }
      .btn {
        width: 150px;
        height: 50px;
        line-height: 50px;
        border-radius: 5px;
        color: #fff;
        text-align: center;
        background-color: #6a48bb;
        background-image: radial-gradient(circle at 50% 50%, rgba(255, 255, 255, 0.7), transparent 70%);
      }
    </style>
  </head>
  <body>
    <div class="btn">发光按钮</div>
  </body>
</html>
